Surface Areas & Volumes | Exercise 13.5 | Q4

Question 4: Find the cost of digging a cuboidal pit 8 m long, 6 m broad and 3 m deep at the rate of Rs.30 per m³.

Explanatory Answer | Class 9 Math Exercise 13.5 Q4

Length of the cuboidal pit, l = 8 m
Width of the cuboidal pit, b = 6 m
Depth of the cuboidal pit, h = 3 m

Volume of the cuboidal pit = l × b × h
= 8 × 6 × 3
= 144 m³
Cost of digging the pit at Rs.30 per m³ = 144 × 30
= Rs.4320

Exercise 13.1 | Surface Area of Cubes & Cuboids

1. Class 9 Exercise 13.1 Question 3 | Height of hall ▶
2. Class 9 Exercise 13.1 Question 6 | TSA of Herbarium ▶
3. Class 9 Exercise 13.1 Question 7 | Shanti Sweets ▶

Exercise 13.2 | Surface Area of Cylinders

1. Class 9 Exercise 13.2 Question 3 | CSA TSA of Metal Pipe ▶
2. Class 9 Exercise 13.2 Question 4 | Roller & Playground ▶
3. Class 9 Exercise 13.2 Question 9 | Cylindrical Petrol Tank ▶
4. Class 9 Exercise 13.2 Question 10 | CSA of Decorative Lampshade ▶

Exercise 13.3 | Surface Area of Cones

1. Class 9 Exercise 13.3 Question 5 | Length of Tarpaulin 3 m wide ▶
2. Class 9 Exercise 13.3 Question 8 | Cost of painting conical barricades ▶

Exercise 13.4 | Surface Area of Spheres & Hemispheres

1. Class 9 Exercise 13.4 Question 8 | Outer CSA of hemispherical bowl ▶
2. Class 9 Exercise 13.4 Question 9 | Surface area of sphere & Cylinder ▶